Typically, planning consent is not necessary for a shed or outbuilding, if its proposed floor area is below 15 square metres, it does not include sleeping accommodations, and the whole structure does not exceed a height of 2.5 metres (if it is located within 2 metres of the property boundary).
Projects that change the configuration of walls, pipes, wiring, roofs, or major appliances typically DO require at least one type of building permit. Projects that DO NOT need a building permit are simple surface (cosmetic) projects; minor repairs and replacements; and minor site improvements or small structures.
Types of Projects That May Be Exempt From a Building Permit in California Painting. Floor upgrades. Kitchen remodels. Small drywall projects. Common electrical work. Small outbuildings. Bathroom fixes. Fences.
Per the California Residential Code detached accessory structure not exceeding 120 square feet does not require a building permit if there is no plumbing, electrical, and or mechanical equipment.
The quick and simple answer is: you usually don't need a permit if the shed is 120 square feet or less. In California, most jurisdictions have adopted the 120 square foot rule. If your shed area is larger than 120 square feet, it needs a building permit.
One-story detached accessory buildings used as tool and storage sheds, playhouses, and similar uses, provided the floor area does not exceed 120 square feet, do not require a Building Permit (per California Building Code 105.2 "Work Exempt from Permit").
In the City of Los Angeles, if the size of floor space exceeds 120 sq. ft. or the structure is over 12 feet in height, you need a permit. Any electrical work will require an electrical permit.
Projects that DO NOT need a building permit are simple surface (cosmetic) projects; minor repairs and replacements; and minor site improvements or small structures.
Do You Need A Permit To Remodel A Bathroom In California? Yes, permits are required for all aspects of remodeling a bathroom. This includes making any additions or modifications that involve construction, electrical wiring, plumbing structures, and other mechanical processes.